Tong guard



y July 4; 1944. E. F. coDNER ToNG GUARD Filed Aug. 11, 1941 will m f a \l .150W/Af FI 600A/ER INVENTOR Arron/viv.

Patented `luly 4, 1944 UNITED STATES PATENT OFFlCE 'roNG GUARDv Edwin F. Codner, Ventura, Calif.. assignor to Byron Jackson Co., Huntington Park,-Calif., a corporation of Delaware Application August 11, 1941, Serial No. 406,307 i 4 claims. (01.81-66) l This invention relates generally to pipe tongs of the type employed for making up and breaking out joints of drill pipe and well casing. It is directed particularly to an improved tong embodying a novel safety feature designed to protect the operator from a hazard which may arise under certain circumstances.

- In accordance with present-day practice, every rotary well-drilling rig includes as an essential part of its equipment 'a pair ,of drill pipe tongs, one right-hand and the other left-hand, for making up and breaking out the tool joints connecting the drill pipe sections. The tongs are suspended in the derrick from counterbalanced lines in order to be capable of vertical adjustment, thus permitting each tong to be applied to either the upper or the lower section of the tool joint. The vertical adjustment also enables the tong applied to the upper tool joint'section to move vertically with the joint section as the later is threaded into or out of engagement with the lower tool joint section.

When making up a jointfit is customary to `first spin the joint up reasonably tight by means of a spinning rope wrapped around the upper joint section. The right-hand, or lead, tong is then applied to the upper joint section and a pull is exerted on the tong lever to make the joint up to the desired degree of tightness, the lower joint section meanwhile being held against rotation by the left-hand, or break-out, tong. When breaking out a joint, the relative positions of the tongs are reversedthat is, the break-out tong is applied to the upper joint section and power is applied thereto, while the lead tong grips the lower joint section and serves as a back-up tong to prevent rotation. Tool joint threads have a relatively steep pitch and considerable taper, and consequently when the joint has been broken'by approximately a quarter-turn, the unscrewing torque decreases rapidly. It is customary to spin the joint out by rotating the rotary table and the pipe supported thereby in a lclock-wise direction, meanwhile leaving the break-out tong clamped to the upper joint section to serve as a back-up tong. It is in connection with the latter practice that a hazard occasionally arises', against which the instant invention'was developed as a safeguard.

Rotary tables are seldom if ever equipped with friction braking means, and hence their rotation is Vnot under full control of the driller. When spinning out a joint, the rotation of the table continues for several revolutions after the power has been cut off and after .the joint has been broken, due to the inertia of the heavy rotating mass. It will be apparent that if, during the rotation of the rotary table and drill string, the' break-out tong should slip down over the rotating lower joint section and grip the joint, serious consequences might result; If the table is rotatsoY ing'-rapid1y, the sudden gripping ofthe tong may sever the tong line and allow the tong to spin around with the pipe, inflicting injury on vanyone in the path ofthe tonglever.

If the ltongs are properly counterbalanced and other equipment Vis inproper operating condition, and if the proper tension is maintained lon the relief spring in the drilling hook during the breaking-outoperation, ythe break-out tong should not slip down ontothe lower joint. However, the hazard exists so long as it is even remotely? possible for the tong to contactand grip the lower joint section while it is rotating. It is not Vpractically feasible to eliminate -all possibility of the tong moving "downward, but it is possible to deprive this contingency of any seriousconsequences by preventing-the tongV` frominadvertently gripping the lowerjoint section. f

A principal objectof ltl'iis invention=isto provide means-whereby a Vpipe tong is prevented from inadvertently gripping one" section of the pipe joint, withoutinterfering with its ability togrip the other joint section. v

l A further Objectis to -provide ajpipe tong vernbodying-adjustable guard 4means operable, when in one adjusted position, to prevent gripping engagement of the tong with a selected pipe joint section, and adjustable at will into another position wherein it permits gripping of the joint section. v f -Y l l A still 'further object of the invention is to provide a pipe tong guard which-may-be quickly and easily applied-to existing tongs at the site of oper' ations, without modicationof the tong structure.

The manner `in which the foregoing andother objects -are accomplished will beapparent from the following detaileddescriptionr of one-embodiment of the inventionfreference being had to the accompanying drawing wherein:

Fig..1 is a top yplan-view of'a tong embodying the invention; 1

Fig. 2 is a View, partly in velevation and partly in vertical sectionVtakenvon line Il-II of Fig. 1 and illustrating .the tong in gripping engagement with the upper vsection of a tool joint; y Fig. 3 is a plan viewzgenerally similar to Fig. 1, but showing the tongv in a position wherein the gripping dies are held out of gripping engagement with the jointby the guard means; f

Fig. 4V is a view corresponding to Fig.y V2 and taken on line IV--IV ofv Fig. 3, .showingfthe tong in lower positionwherein the guard means er1--l gage the. upperjointsectionand prevent the dies from grippingthe lower Ijoint section; Fig. 5 is atop plan view of a modiedguard construction; and Y Fig, 6 isa vertical section taken Referring to Fig.v 1 ofthe drawinghevnovel concave and substantially concentric with the curvature of the pipe.

It is also within the purviewof this invention .to mount the guard plates on the"upper ends of the hinge' pins for angular adjustment with re- .,spect to the pins, an expedient which would be The outer ends of the outer^--= jaws I6 and I1 are detachably connected 'by a' latch 2|! pivotally mounted on one jaw and engaging a. latching surface on the other jaw. `The pivot pins I3 and I4 are spaced apart 4longitu-v r`r Amethfodfof thus mounting the guard plates. The plate 35 isv generally similar in shape to the plates dinally of the lever` I5 whereby swinging move-'I" ment of the lever in the direction of thearrow ,f P causes the jaws to constrict about the pipe joint l and force the gripping dies 2| and 22 mounted in jaws II and I2 intoggripping engagement vwith iheJ'Oint- The. novel guard means provided by the instant invention may comprise a plurality of plates 25 and 26 mountedon the-upper side of the tong in a, position to normally projectY substantially radially inwardly into the VVpipebore deinedV by the jaws. It will be observed that the inner edges of the guard platesl project farther into the bore than Vdo the teeth ofi, the dies 2l and22, Iand hence in order that the jaws may beconstricted about the joint suiciently to cause the dies to grip the joint, it is necessary that the tong be positioned on the pipev substantially: as shown in Fig. 2, with the guard plates "overlying the upper tcol joint section 21.

AAATheguard plates 25'far1d'26A are preferably mounted on the upper lends o f the jaw hinge pins I8 and I8, respectively, -andnalso are preferably, althoughk not necessarily, rigidly secured thereto, asby. welding as shown at 428. With this .arrangement, the plates maybe quiclsly and easily applied to a tong at the drilling site'bylhe simple expedient of replacing the regular `hinge pins by the two special pins with the plates attached thereto. .t w A,

`As was pointed out in the introductory remarks, the left-hand or break-cutr tong must also be capable of applicatiomtorthe lower tool joint section 29 for use as a back-up tong when making up tool joints. For this reason, it is ess ential that the guardplates 25 and 26 bev capable of being renderedinoperative when desired. `By mounting the plates on the hinge pins, they may be,A rotated about theuaxes of thepins into the dotted-line positions indicated at 2,5 and 26 in ZEig.r l. It is'only necessary to loosen the hinge pin retaining nuts 30 suiflciently to permit rota-v tion of the hinge pins, and upon subsequent tightening of thenuts the hingel pins and consequently the guard plates are held in adjusted position by the frictionalengagement.of the nuts andthe plates with the opposite faces of the jaws. If preferred, means maybe provided for positively locking theA hinge pins and plates in either of two adjusted positions, although'I have found from experience that this is not necessary. .l

. It will be observed thatthe inner edges 3| .of

the guard plates are arcuate'in plan view and areconcentric with'the axes of the hinge pins on which the plates are mounted. ln this manner` considerable angular variation in the `operative positions of the plates'is permissible without changing the extent ofv inward projection ofthe plates. It is not-essential, however, that the Vinner edges of the plates be oftheabcve-noted confluratio'n; and this is especially true'i'fjthe plates are positively locked in predetermined op# erative pc'isitio'nf Forexan1ple,"the edges may'be 7 5 vdesirable in applying the invention to tongs in which the hinge pins are held against rotation with respect to one of the jaws. In Figs. 5 and 6QI have illustrated 'a convenient and inexpensive The outer portion of the plate,4 however, is slotted to provide two spaced ears or lugs 36 and 31 which are bored to receive a retaining bolt 38. As shownmost clearly. in Fig. 6, an arcuate grooveV 33.is formed circumferentially about the upper portion of the hinge pin I9', to partially receive theV retaining bo1t3v8 and thus lockrrthe zguard plate againstrelative upward movement with respect to the hinge pin, while at the same time permitting the plate to assume any desired angularly adjusted position about the axis of the pin. By tightening the nut 4U on the retaining bolt, theY plate may be securely clamped tothe vhinge pin, the lugs 36 and 31 having sufficient resiliency to permit their flexing to attain this result. Y Y' u ,A

The operation of the guardv and the manner. in which it performs .its intended function willbe apparent from a comparison of Figs. 1 and 3 land of their corresponding elevational views shown in Figs. 2 andWhen withdrawingthe string of drill pipe from the well, it is raised by the hoisting mechanism until the jointto be broken is slightly above the Arotary table, and theslips are set to support the pipe in the table. The break-out tong is then applied to the upper Ajoint section 21 in the position shown inV Fig. 2, and the lead tong is .applied `to the lower joint section 29l to prevent its rotation while V'poweris applied from the usual automatic cathead to thebreakout tong to break the joint by counter-clockwise rotation of the upper joint section. With the breakfout tong in the position shown in Fig. 2, the guarda'plates overlie the upper joint section and vhave sufficient clearance with the drill pipe to permit the tong jaws to constrict about the joint section 21 and force the dies 2| and 22 into gripping engagement with the joint.

After the' joint `has been loosenedby rotation through approximately a 'quater-turn, the lead tong is then removed from the lower joint sec tion andthe rotary table is rotated in clockwise direction through the usual 'drive mechanism. The' .breakf-out tong is retained on the up`per jointsection as a back-up tong to preveniro` tation'of the stand of pipe being broken out,l the tong linel extending to the automatic Vcathead serving asa back-up' line; During thisI operaation the friction between -the'threads'of the joint sections transmits sufficient torque from the rotating lower section tothe stationaryupper sec tion to maintain the tong line taut and the tong jaws constricted about the upper joint. v It is obvious, therefore, that during the spinning out operation the break-out tong is prevented by the guard plates 25 and 26 ffrom'slippingA down-along the upper joint section andv into engagement with the lowerk joint section. A t 'j Y f f After ,the threadsof the'joint sections lare com; pletely disengaged, howev'enthe upper joint secV tion'is relieved ofthezcounter-clockwise torque imposed bythe spinningflower section, andthe only force tendingto maintain the tongoonstrictgL ed about the joint is the weight oi the slack tong line. Ordinarily, this is suilicient to prevent the tong from opening up suiciently to allow the guard plates and 26 to clear the joint section 21 and permit'the tong to move downwardly into the position shown in Fig; 4. However, if this should occur, it will be apparent that no harm would result inasmuch as the guard plates would then come into contact with the peripheral surface of the upper joint section 21 and would prevent the tong jaws from constricting suiciently to permit the dies to contact and grip the spinning lower joint section. This condition is most clearly illustrated in Fig, 3, wherein it will be observed that the dies 2l and 22 are held out of contact with the joint by engagement of the guard plates 25 and 26 with the joint at one side of the dies and .by engagement of the heels of the jaws Il and l2 with the joint at the opposite side of the dies.

It is therefore apparent that if from any cause the break-out tong should move downwardly around the lower joint while the latter is rotating, the tong dies cannot grip the joint and cause the tong to spin about the axis of the pipe. The frictional contact of the guard plates and the heels oi the jaws with the joint is insucient to exert any substantial torque on the tong.

In addition to the foregoing safety feature, the provision of the guard plates also eliminates the possibility of tong breakage and possible injury to the crew as the result of inadvertently placing the tong on the pipe in too low position. It occasionally happens that the break-out tong is placed on the pipe so low that it overlaps the lower tool joint section, which is also gripped by the lead tong during the initial breaking-out step. 1f this occurs and the dies in the break-out tong are permitted to grip the lower joint, it is obvious that the two tongs cannot turn relative to each other. and, if the usual amount of power is applied to the break-out tong, one of the tong lines or levers will be broken.

From the foregoing description of one embodiment of the invention and a modification thereof, it will be apparent that a safety device has been provided which is effective in eliminating a hazard which, although of infrequent occurrence, is very likely to cause serious injury to the drilling crew if it does occur.

I claim:

1. A pipe tong for use on sectional pipe joints of greater external diameter than the pipe sections joined thereby, comprising a lever, jaws mounted thereon, a pipe-gripping die in one of said jaws, and a guard member mounted on said tong in a plane above said die and having a portion thereof projecting radially inwardly beyond said die, the projecting portion of said guard member being adapted to normally overlie the pipe joint to permit gripping engagement of said die -with the upper pipe joint section, said guard member being so located with respect to said die as to cause said -guard member to engage the peripheral surface of the upper pipe joint section and thus prevent gripping engagement of said die with the lower pipe joint section when the tong is in an abnormal lower position, said guard member being adjustably mounted onsaid tong for adjustment into an inoperative position disposed radially outwardly of the gripping portion of said die.

2. A pipe tong for connecting and disconnecting pipe sections having pipe joints of greater external diameter than the pipe, comprising: a lever, a series of pivotally interconnected jaw segments dening a pipe opening therebetween; means pivotally connecting the end segments of the series to the lever at spaced points thereon, whereby swinging movement of the lever constricts or loosens the segments about a pipe joint positioned in the pipe opening; a gripping die mounted in one of said segments in position to be forced into gripping engagement with the pipe joint upon constriction of the jaw segments; a guard member mounted on said tong and having a portion thereof projecting into said pipe opening radially inwardly of said die and in a plane above said die, the projecting portion Aof said guard member being adapted to normally overlie said pipe joint and permit said die to engage said pipe joint when the tong is in proper position thereon, said guard member being so located with respect to said die as to cause said guard member to engage the peripheral surface of the pipe joint and prevent gripping engagement of the die therewith when the tong is applied thereto in an improper lower position, said guard member being adjustable at will into an inoperative position wholly outside said pipe opening to permit application of said tong to a pipe joint with the guard member disposed in a plane below the upper extremity of said joint.

3. A pipe tong for use on sectional pipe joints of greater external diameter than the pipe sections joined thereby, comprising a lever, a series of pivotally interconnected jaw segments mounted thereon and defining a pipe opening, hinge pins pivotally interconnecting said segments and said lever, a pair of said hinge pins being disposed on substantially opposite sides of said pipe opening, a gripping die adjacent each of said pair of hinge pins, and a guard member mounted on each of said pair of hinge pins and having portions normally projecting into said pipe opening radially inwardly beyond said dies, the projecting portions of said guard members being adapted to normally overlie the pipe joint to permit gripping enga-gement of said dies with the upper pipe joint section, said guard members being so located relative to the respective dies as tf. cause said guard members to engage the peripheral surface of the upper of said pipe joint sections and thus prevent gripping engagement of said dies with the lower pipe joint section when the tong is constricted about the pipe joint in an abnormally low position.

4. A pipe tong for use on sectional pipe joints. comprising a lever, a series of pivotally interconnected jaws mounted thereon and defining a pipe opening, pipe-gripping dies in certain of said jaws, a pair of guard members mounted on said tong on opposite sides of said pipe opening, each of said guard members having a portion thereof projecting into said pipe opening radially inwaldly beyond a respective one of said dies, said guard members being so located relative te the respective dies as to cause said guard members to engage the peripheral surface of the pipe joint and thus prevent constriction of the jaws su'b ciently to cause said dies to grip the pipe joint Iwhen the tong is incorrectly applied to the pipe joint in an abnormally low position.

EDWIN F. CODNER. 

